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/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
//-----------------------------------------------------------------------------
var BUGNUMBER = 505587;
var summary = 'ES5 Object.getOwnPropertyDescriptor(O)';
var actual = '';
var expect = '';
printBugNumber(BUGNUMBER);
printStatus (summary);
/**************
* BEGIN TEST *
**************/
function assertEq(a, e, msg)
{
function SameValue(v1, v2)
{
if (v1 === 0 && v2 === 0)
return 1 / v1 === 1 / v2;
if (v1 !== v1 && v2 !== v2)
return true;
return v1 === v2;
}
if (!SameValue(a, e))
{
var stack = new Error().stack || "";
throw "Assertion failed: got " + a + ", expected " + e +
(msg ? ": " + msg : "") +
(stack ? "\nStack:\n" + stack : "");
}
}
function expectDescriptor(actual, expected)
{
if (actual === undefined && expected === undefined)
return;
assertEq(typeof actual, "object");
assertEq(typeof expected, "object");
var fields =
{
value: true,
get: true,
set: true,
enumerable: true,
writable: true,
configurable: true
};
for (var p in fields)
assertEq(actual.hasOwnProperty(p), expected.hasOwnProperty(p), p);
for (var p in actual)
assertEq(p in fields, true, p);
for (var p in expected)
assertEq(p in fields, true, p);
assertEq(actual.hasOwnProperty("value"), actual.hasOwnProperty("writable"));
assertEq(actual.hasOwnProperty("get"), actual.hasOwnProperty("set"));
if (actual.hasOwnProperty("value"))
{
assertEq(actual.value, expected.value);
assertEq(actual.writable, expected.writable);
}
else
{
assertEq(actual.get, expected.get);
assertEq(actual.set, expected.set);
}
assertEq(actual.hasOwnProperty("enumerable"), true);
assertEq(actual.hasOwnProperty("configurable"), true);
assertEq(actual.enumerable, expected.enumerable);
assertEq(actual.configurable, expected.configurable);
}
function adjustDescriptorField(o, actual, expect, field)
{
assertEq(field === "get" || field === "set", true);
var lookup = "__lookup" + (field === "get" ? "G" : "S") + "etter";
if (typeof o[lookup] === "function")
expect[field] = o[lookup](field);
else
actual[field] = expect[field] = undefined; /* censor if we can't lookup */
}
/******************************************************************************/
var o, pd, expected;
o = { get x() { return 12; } };
pd = Object.getOwnPropertyDescriptor(o, "x");
expected =
{
set: undefined,
enumerable: true,
configurable: true
};
adjustDescriptorField(o, pd, expected, "get");
expectDescriptor(pd, expected);
/******************************************************************************/
var o2;
o = Object.create(Object.prototype, { x: {get: function () { return 12; } } });
pd = Object.getOwnPropertyDescriptor(o, "x");
expected =
{
set: undefined,
enumerable: false,
configurable: false
};
adjustDescriptorField(o, pd, expected, "get");
expectDescriptor(pd, expected);
o2 = Object.create(o);
assertEq(Object.getOwnPropertyDescriptor(o2, "x"), undefined);
/******************************************************************************/
o = {};
o.b = 12;
pd = Object.getOwnPropertyDescriptor(o, "b");
expected =
{
value: 12,
writable: true,
enumerable: true,
configurable: true
};
expectDescriptor(pd, expected);
/******************************************************************************/
o = { get y() { return 17; }, set y(z) { } };
pd = Object.getOwnPropertyDescriptor(o, "y");
expected =
{
enumerable: true,
configurable: true
};
adjustDescriptorField(o, pd, expected, "get");
adjustDescriptorField(o, pd, expected, "set");
expectDescriptor(pd, expected);
/******************************************************************************/
o = {};
pd = Object.getOwnPropertyDescriptor(o, "absent");
expectDescriptor(pd, undefined);
/******************************************************************************/
pd = Object.getOwnPropertyDescriptor([], "length");
expected =
{
value: 0,
writable: true,
enumerable: false,
configurable: false
};
expectDescriptor(pd, expected);
pd = Object.getOwnPropertyDescriptor([1], "length");
expected =
{
value: 1,
writable: true,
enumerable: false,
configurable: false
};
expectDescriptor(pd, expected);
pd = Object.getOwnPropertyDescriptor([1,], "length");
expected =
{
value: 1,
writable: true,
enumerable: false,
configurable: false
};
expectDescriptor(pd, expected);
pd = Object.getOwnPropertyDescriptor([1,,], "length");
expected =
{
value: 2,
writable: true,
enumerable: false,
configurable: false
};
expectDescriptor(pd, expected);
/******************************************************************************/
pd = Object.getOwnPropertyDescriptor(new String("foobar"), "length");
expected =
{
value: 6,
writable: false,
enumerable: false,
configurable: false
};
expectDescriptor(pd, expected);
/******************************************************************************/
function foo() { }
o = foo;
pd = Object.getOwnPropertyDescriptor(o, "length");
expected =
{
value: 0,
writable: false,
enumerable: false,
configurable: true
};
expectDescriptor(pd, expected);
pd = Object.getOwnPropertyDescriptor(o, "prototype");
expected =
{
value: foo.prototype,
writable: true,
enumerable: false,
configurable: false
};
expectDescriptor(pd, expected);
/******************************************************************************/
pd = Object.getOwnPropertyDescriptor(Function, "length");
expected =
{
value: 1,
writable: false,
enumerable: false,
configurable: true
};
expectDescriptor(pd, expected);
/******************************************************************************/
o = /foo/im;
pd = Object.getOwnPropertyDescriptor(o, "lastIndex");
expected =
{
value: 0,
writable: true,
enumerable: false,
configurable: false
};
expectDescriptor(pd, expected);
/******************************************************************************/
reportCompare(expect, actual, "Object.getOwnPropertyDescriptor");
printStatus("All tests passed");